The statements in this section provide background information related to the present disclosure and do not constitute prior art.
With the exhaustion of the global energy resources and the growing emphasis on environmental protection, electrical vehicles (EV) and hybrid electrical vehicles (HEV) have drawn much attention due to the advantages such as low exhaust emissions and low energy consumption etc. In recent years, more and more companies and research institutes have successively invested in the researching as well as marketing in EV and HEV. It has been found that during the researching of electrical vehicles and hybrid electrical vehicles, the power battery technology is one of the key elements that may restrict the development of the new energy vehicles.
In EV, HEV or similar vehicles, a lithium ion battery with high power may normally be used as a power battery to satisfy high output requirements. As the power battery in the vehicle has a higher discharging rate, the lithium ion battery may produce a large amount of heat in the rapid discharging process. When the temperature is increased, the lithium ion battery may run in a severely uneven state, thus directly affecting the battery life span and producing serious potential safety hazard. Therefore, to ensure that the lithium ion battery runs in a favorable temperature condition, excellent heat dissipation for the lithium ion battery is needed.
Moreover, because, as an energy storage device, the power battery plays a critical role in EV, HEV or similar vehicles, the performance of the power battery greatly affects the performance of the whole vehicle. The power battery is normally formed by a plurality of single cells connected in serials, in parallel, or in serials and parallel. Currently, single cells may not work normally at low temperature, e.g., a temperature lower than −20° C. or high temperature e.g., a temperature higher than 45° C., and thus the vehicle using the power battery may not work normally.